gemstone

Carnelian Agate

SiO2 (Silicon Dioxide - Chalcedony variant)

Hardness: 6.5-7 on Mohs scale. Color: Orange, reddish-brown, to translucent honey-amber. Luster: Vitreous to waxy. Crystal system: Trigonal (microcrystalline quartz). Specific gravity: 2.58-2.64.

Hardness: 6
Color: Orange, reddish-brown, to translucent honey-amber
Luster: Vitreous to waxy

Identified July 22, 2026More gemstone →

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Physical properties

Hardness: 6.5-7 on Mohs scale. Color: Orange, reddish-brown, to translucent honey-amber. Luster: Vitreous to waxy. Crystal system: Trigonal (microcrystalline quartz). Specific gravity: 2.58-2.64.

Formation & geological history

Formed through low-temperature precipitation of silica-rich solutions within cavities of volcanic basaltic or metamorphic rocks. Heat treatment (natural solar or artificial) often enhances the deep red-orange color due to iron oxide impurities.

Uses & applications

Extensively used in jewelry making (beads, cabochons, carvings, signet rings) and lapidary art. Highly valued by mineral collectors for its translucent, warm coloration.

Geological facts

Carnelian has been used as a gemstone for over 4,500 years. Ancient Romans and Egyptians crafted lapidary seals and amulets from it, as hot wax did not stick to polished carnelian.

Field identification & locations

Identified by its waxy-to-glassy luster, conchoidal fracture, hardness (scratches glass), and distinctive translucent reddish-orange body color. Commonly found in Brazil, India, Madagascar, Uruguay, and parts of the United States.

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